Auxiliary combustion chamber for internal combustion engines



G. L. RILEY May 24, 1938.

AUXILIARY COMBUSTION CHAMBER FOR INTERNAL COMBUSTION ENGINES Filed Jan. 24, 1956 r i n +4 I n... PM, p V

Patented May 24, 1938 UNITED STATES AUXILIARY COMBUSTION CHAMBER FOR INTERNAL COMBUSTION ENGINES Glenn L. Riley, New Orleans, La., assignor, by

direct and mesne assignments, to Riley Dirvelopment Corporation, a corporation of Luisiana Application January 24, 1936, Serial No. 60,693

4 Claims.

This invention relates to new and useful improvements in the combustion chambers of internal combustion engines.

The main object of the invention is to provide the combustion chamber of an internal combustion engine with auxiliary fuel and ignition chambers designed to effect ignition and rapid burning of the fuel in the engine cylinder with approximately constant compression at all speeds of the engine.

Another object of the invention is to provide an attachment adapted to be secured in the spark plug opening of internal combustion engines, to make possible the satisfactory use of low grade iuel oil in internal combustion engines using the regular electrical ignition systems designed for use on engines using gasoline only.

Other objects of the invention will appear as the following description of a preferred and practical embodiment thereof proceeds.

In the drawing: Figure 1 is a fragmentary vertical section through the upper part of the cylinder and the cylinder head of an L-head internal combustion engine, with the present invention applied as an attachment thereto;

Figure 2 is a central vertical section, to an enlarged scale, of the said attachment;

Figure 3 is a vertical transverse section taken on the line 33 of Figure 2;

Figure 4 is a bottom plan view of the attachment as shown in Figure 2;

Figure 5 is a central vertical section through a modified form of the said attachment;

Figure 6 is a central vertical section of another modified form of the invention;

Figure 7 is a horizontal section taken on the line 2-1 of Figure 6;

Figure 8 is a central vertical section through still another modification of the invention;

Figure 9 is a horizontal section taken on the line 99 of Figure 8; and

Figure 10 illustrates a form of the invention similar to that shown in Figure l of the drawing,

but in which the improvement is made integral with the cylinder head.

In Figure 1 of the drawing, the reference numeral ll indicates the cylinder block, provided with the cylinder bore 12 in which the piston. 13 is adapted to reciprocate in the usual manner to convert its reciprocating motion through connecting rod it into rotary motion of a crank shaft (not shown). The upper end of the block H has the head i5 suitably and detachably secured thereto. As usual in devices of this character, the head I5 is provided with a clearance space It forming part of the combustion chamber and extending substantially over the greater part of the cylinder bore l2 to connect with the main part1! of the said combustion chamber The main part I1 of the combustion chamber is located above the intake port [8 which is controlled by a poppet valve l9 normally closed by a spring 29 and opened by the usual tappet and cam shaft mechanism (not shown). It will be understood, of course, that the block is provided with the usual exhaust valve operated in properly timed relation with the intake Valve l9.

Directly above the chamber 11, the cylinder head 15 is provided with an internally screwthreaded aperture 2| adapted to receive the externally screwthreaded end 22 of a fitting 23 cast to form auxiliary fuel and ignition chambers. The aperture 2| may be the aperture commonly provided in the cylinder heads to receive a spark plug, or the fitting 23 may be cast integral with the cylinder head as shown in Figure 10 of the drawing.

The, fitting 23 is provided at its upper end with a laterally extending boss 24, internally screwthreaded to receive a spark plug 25 of usual construction. The boss 24 and the upper end of the fitting 23 are bored to form a cylindrical primary ignition chamber 26 having its axis substantially parallel to the cylinder head. The fitting 23 is cast to form a conical fuel chamber 21 communicating at its lower and wider end with the combustion chamber I1, and at its upper end with the primary ignition chamber 26.

As will be apparent from Figure 3 of the drawing the axis of the conical fuel chamber 2'! is inclined to the axis of the fitting so that vaporized liquid fuel is passed into the primary ignition chamber 26 substantially at a tangent to the cylindrical wall of the said chamber. It will be apparent from Figures 1 and 2 of the drawing that when the vaporized liquid fuel in the chamber H is compressed, part of that vaporized fuel will be forced through the restricted opening 28 at the upper end of the conical chamber 21 at greatly increased speed tangentially against the cylindrical wall of the ignition chamber 26; This injection of the fuel sets up a whirling or turbulence of the vaporized fuel in the chamber 26, causing the heavy particles of the fuel to whirl around the cylindrical wall of the chamber. The more gaseous part of the fuel is concentrated nearer to the center of the chamber, and with a somewhat increased temperature is in condition to be ignited by a spark from the electrodes of the spark plug 25.

The ignition of the gas in the chamber 26 immediately sets up a rapid burning of the gas or vapor in the auxiliary combustion chamber 21; and this burning gas is projected forcibly through chamber 27 into the combustion chamber Ii. Since the chamber 21 is wider at its lowest end, the igniting flame is greatly expanded and contacts with the fuel in chamber I! over a comparatively large area and sets up a rapid. burning of the fuel in the cylinder.

The form of the invention illustrated in Figure 5 is substantially the same as that shown in Figures 1, 2 and 3. The fitting 29, however, is screwthreaded at its upper end to receive the spark plug which seats in the upper end with its axis substantially in alignment with the axis of the fitting.

The form of the invention shown in Figure 6 of the drawing is similar to that shown in Figure 5 except that the fitting 36 shown in Figure 6 has a spherical ignition chamber 3| instead of a cylindrical chamber shown in the preceding figures of the drawing.

The form of the invention shown in Figure 8 includes a fitting 32 adapted to be detachably secured in the spark plug opening. In this form of the invention, the auxiliary fuel chamber 33 has its axis extending substantially perpendicular to the cylinder head; and, communicates at its upper end with a cylindrical ignition chamber 34 having its axis coincident with the axis of the conical chamber 33. The upper end of the chamber 34 is screwthreaded to receive a spark plug having its axis aligned or coincident with the axis of the said ignition chamber 34.

The fitting 23, 'or the other fittings corresponding thereto, should be of sufficient length to locate the spark plug at some substantial distance from the comparatively hot cylinder head; and, the material of the fitting should be such as to radiate heatrapidly in order to avoid excessive heating of the vaporized fuel during its passage to the spark plug ignition chamber. The length 7 of theauxiliary fuel chamber and the cross sectional area of the aperture 28 will vary with the size of the engine to which the invention may be applied; and, must be determined empirically in order to produce the best result. The base of the cone forming thelower end of the fuel chamber 2! should be'as large as possible in order that the flame issuing therefrom might impinge on large areas of the vaporized'fuel in chamber I1. It is essential in all cases that the aperture 28 be restricted sufliciently in comparison with the cross auxiliary combustion and ignition chambers in the fitting forming the subject matter of this invention. However, as the result of experimenting with many models of various'dimensions, a fitting of the type shown in Figure 1 and having the following dimensions was found satisfactory:

- Inches 1. Diameter of lower open end of chamber 2L 2. Diameter of upper end of chamber 2'I 3. Length of chamber 21 2' 4. Length of ignition chamber 26 1 5. Diameter of chamber 26 A 'known as saturated or wet.

The diameter of the lower end of the chamber 21 is substantially the same as that of the electrode casing of practically all spark plugs. The diameter of the auxiliary ignition chamber 26 is the same. These dimensions are obviously required, since the fitting is intended to replace the spark plug on the cylinder head, and the chamber 26 is designed to receive a similar spark plug. Variations of dimensions will be necessary when adapting the fitting to existing engines, but new engines may be provided with standard fittings of the most efficient type and size.

It will be understood that the dimensions of the fittings will vary with the different makes of cars and engine sizes. In any case, the various elements of the fittings should be varied correspondingly to give the best results. It is not absolutely necessary that the auxiliary fuel chamber should be conical; it may be cylindrical or a close approximation to cylindrical. In 'all cases, it is essential that the passageway from the combustion chamber of the cylinder shall be restricted relatively to the diameter of the auxiliary ignition chamber, in order that the compressed liquid fuel will be projected into the said ignition chamber with such force as to cause the heavier particles of the vaporized liquid fuel to whirl around against the wall of the said chamber, with the central part of said liquid gasified, and adjacent to the electrodes of the spark plug. It is preferable, however, to have the fuel chamber 21 made conical in order that the flame resulting from the ignition of the gas in the chamber 26 shall have the greatest area of contact with the vaporized fuel in the combustion chamber in the cylinder head.

The theory of operation of the device is as follows: V

The supply of fuel in the form of atomized oil mixed with the proper proportions of air having been drawn into the motor cylinder in the usual manner, after passing through the carburetor, or through a mixing valve, is still in non-explosive form. The mixture is then in the condition As the piston comes up on the compression stroke it forces a quantity of this wet mixture into the auxiliary fuel chamber of the device. The decreasing cross sectional area of this fuel chamber causes the mixture to travel faster as it progresses'toward the primary ignition chamber-until high velocity of the entering mixture is attained, and it strikes the curved surface of the primary ignition chamber at high speed.

The atomized oil is forced into the primary ignition chamber so rapidly through the small opening at the end of the fuel chamber that it is vaporized and is now in explosive form. Inthis primary ignition chamber the fuel, now vaporized, is ignited by an electric sparkand converted into flame. Should any of the particles of fuel fail to be vaporized in their travel through the fuel chamber, they are thrown against the inner surface of the primary ignition chamber by centrifugal force, assuring positive non-fouling condition for the spark plug or sparking device, but said particles will ignite when the vaporized fuel has been converted into a flame. 1

The fact that the fuel particles rotate at high speed in the primary ignition chamber and thus produce a low pressure area at their vortex or center allows the spark plug or sparking device to operate at better advantage. As electrical resistance is governed by pressure, the spark will take place more readily in this low pressure area.

ISO

Since the fuel in the primary ignition chamber is then vaporized and highly combustible, when the spark occurs the charge in the primary ignition chamber ignites. As it ignites, it expands, increasing the pressure in the primary ignition chamber during its expansion. The flame travels back down the connecting passage, through the fuel chamber and into the engine combustion chamber, and ignites the charge in the cylinder, causing the full charge to burn very rapidly. The expansion of the burning gases forces the piston down and turns the engine shaft in the usual manner to derive power from the fuel. It will be noted that an explosion does not occur in the motor cylinder but instead there is a very rapid burning of the fuel.

While I have in the above description disclosed what I believe to be preferred and practical forms of the invention, it will be understood to those skilled in the art that the specific construction and arrangement of parts are merely by way of example and not to be construed as limiting the scope of the invention as shown in the appended claims.

What I claim is:

1. In an internal combustion engine having a cylinder and a piston operating therein and a head for the cylinder forming a combustion chamber over the piston, a casing connected to the cylinder head and having a cylindrical ignition chamber formed at the end thereof remote from said head, said casing having a conical passageway tangentially communicating with said ignition chamber for conducting vaporized fuel under pressure from the combustion chamber with whirling motion into the ignition chamber, the base of the conical passageway communicating with said combustion chamber, and ignition means coaxial with said ignition chamber for igniting the vaporized fuel.

2. In an internal combustion engine having a cylinder and a piston operating therein and a head for the cylinder forming a combustion chamber over the piston, a casing connected to the cylinder head and having a cylindrical ignition chamber formed at the end thereof remote from said head, the axis of the cylindrical ignition chamber being inclined to the axis of the cylinder, a conical passageway tangentially communicating with said ignition chamber for conducting vaporized fuel under pressure from the combustion chamber with whirling motion into the ignition chamber, the base of the conical passageway communicating with said combustion chamber, and ignition means coaxial with said ignition chamber for igniting the vaporized fuel.

3. In an internal combustion engine having a cylinder and a piston operating therein and a head for the cylinder forming a combustion chamber over the piston, a casing connectedto the cylinder head and having an ignition chamber of circular cross section formed at the end thereof remote from said head, a conical passageway tangential to said ignition chamber for conducting vaporized fuel under pressure from the com,- bustion chamber tangentially against the wall of the ignition chamber, the base of the conical passageway communicating with said combustion chamber, and ignition means coaxial with said ignition chamber for igniting the vaporized fuel.

4. In an internal combustion engine having a cylinder and a piston operating therein, and an intake valve controlling the supply of liquid fuel to said cylinder and a head extending over said cylinder and recessed to form a combustion chamber directly over said piston and valve, a casing connected to the cylinder head directly over said valve and having an ignition chamber of circular cross section formed atthe end there'- of remote from said head, a conical passageway tangential to said ignition chamber for conducting vaporized fuel under pressure from the come bustion chamber, the base of the conical passageway communicating with said combustion chamber, and ignition means coaxial with said ignition chamber for igniting the vaporized fuel.

GLENN L. RILEY. 

